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1.
本文讨论了苎麻纤维分别在120℃、130℃、140℃和150℃干热处理下其结晶度与取向度的变化、强力与伸长的下降以及染色性能的改善。本文采用KES-FB-2纯弯曲试验仪测试了苎麻纤维的柔软性。用弯曲刚度及弯曲滞后矩表述试样的柔软性,对两者进行了比较。经干热处理后苎麻的柔软性亦有所提高。  相似文献   

2.
介绍了羊毛与苎麻两种粗纱的前处理工艺。实验证明,高锰酸钾一蛋白酶改性处理后的羊毛纤维能够去除羊毛的鳞片以消除其对人体的刺痒感,并且保持羊毛的强伸性能不发生明显改变。而碱一纤维素酶改性处理后的苎麻纤维不仅对伸长率、结晶度、取向度与刚度等各方面性能都有较大改善,而且对其后道成纱工艺及服用性能也有一定作用,为夏季用羊毛,苎麻复合纱的开发奠定基础。  相似文献   

3.
不同脱墨方式对二次纤维孔隙结构和结晶性能的影响   总被引:1,自引:0,他引:1  
采用X射线衍射和等温氮吸附法研究了废旧新闻纸(ONP)在不同脱墨方式下孔隙结构和结晶性能的变化,并运用分形理论对纤维的孔隙结构进行了分析.等温氮吸附实验发现,ONP浆经过中性、碱法和酶法脱墨后,其BET比表面积、BJH孔容及BJH平均孔径变化不大.分形分析发现,脱墨前后纤维的分形维数相近,说明三种脱墨方式对纤维的孔隙结构影响较小. X射线衍射实验发现ONP浆经过中性、碱法和酶法脱墨后,结晶度下降,碱法脱墨浆纤维结晶度下降最大,达12.24%,中性脱墨浆下降6.12%,酶法脱墨浆下降最少仅0.77%.研究中还发现,经过脱墨后,纤维的保水值有所增大,其中碱法脱墨浆纤维增加最大,中性脱墨浆次之,酶法脱墨浆最小.  相似文献   

4.
通过X射线衍射分析和低温氮吸附法等方法研究了废旧新闻纸(ONP)浆及经不同脱墨方式脱墨后的脱墨浆的纤维孔隙结构和结晶性能的变化,并运用分形理论对纤维的孔隙结构进行了分析.结果表明:ONP浆经过中性、碱法和酶法脱墨后,其BET比表面积、BJH孔容及BJH平均孔径变化不大;脱墨前后纤维的分形维数相近,脱墨方式对纤维的孔隙结构影响较小;ONP浆经过中性、碱法和酶法脱墨后,结晶度下降,碱法脱墨浆纤维结晶度下降12.24%,中性脱墨浆下降6.12%,酶法脱墨浆下降最少,仅0.77%;经过脱墨后,纤维的保水值有所增大,其中碱法脱墨浆纤维增加最大,中性脱墨浆次之,酶法脱墨浆最小;脱墨后纤维打浆度和平均长度下降较小,细小纤维含量增加.  相似文献   

5.
研究了以N 甲基吗啉 N 氧化物(NMMO)为溶剂的Lyocell纤维纺丝工艺中纺丝速度对Lyocell纤维结构的影响.实验结果表明:随着纺丝速度的提高,Lyocell纤维的结晶度、晶区取向、双折射及无定形取向增大,但当纺丝速度达到50m/min时,纤维的双折射和无定形取向都达到最大值,纺丝速度继续提高,纤维的双折射维持恒定不变,无定形取向反而下降.  相似文献   

6.
研究了热处理时不同的温度、时间及张力对Lyocell纤维结构和性能的影响。结果表明热处理能提高Lyocell纤维的强度和模量,但是断裂伸长率有所下降。热处理温度为160℃,时间为12~25s时效果较好。热处理中施加张力可以进一步提高Lyocell纤维的强度和模量,但纤维的断裂伸长率迅速下降。热处理后的Lyocell纤维结晶度略有提高,但随着张力的增加,结晶度基本不变。热处理后纤维的总取向增大,而晶区取向基本不变,故无定形区取向大幅度提高。研究结果还表明Lyocell纤维通过热处理而提高的力学性能并不能长久地维持,随着放置时间的延长,其力学性能会逐渐下降并回复到热处理以前的状态。  相似文献   

7.
为降低苎麻纤维结晶度,改善其柔软性能,采用N,N-二甲基乙酰胺(DMAc)对苎麻精干麻进行溶胀降晶处理,并研究了处理工艺对苎麻纤维的力学性能与柔软性能的影响.结果表明:随着DMAc质量分数的增加、处理时间的延长和处理温度的升高,苎麻纤维的断裂强度呈下降趋势,断裂伸长率和断裂回转数呈增大趋势,纤维变得柔软;DMAc质量分数为20%、处理时间为2h、温度为80℃为较佳工艺;较佳工艺下处理的苎麻纤维表面粗糙且有裂痕,纤维结晶度由80.73%降至70.36%;NaOH预处理可提高DMAc对苎麻纤维的处理效果,但NaOH质量分数宜控制在5%以内.  相似文献   

8.
碱处理对亚麻纤维性能的影响   总被引:1,自引:1,他引:0  
通过改变碱液浓度、浸碱时间和浴比,采用L9(3^3)正交实验对亚麻纤维进行碱处理工艺优化,研究碱处理对亚麻纤维性能的影响.实验结果表明,经碱液处理后,亚麻纤维的主体纤维比例增大,伸长性提高,并产生大量卷曲,但平均长度减小、强度下降.其中碱液浓度是影响亚麻纤维性能的最显著因素.  相似文献   

9.
将粘胶纤维于不同温度下在甘油中松驰热处理后,用计算机分峰法研究其微细结构的变化及其对性能的影响。已发现,在松驰状态下,在190℃以上温度热处理时,发生结晶度的增加和晶型的转变。结晶度的增加主要是纤维素Ⅳ的增加,而纤维素Ⅳ的形成包括由无定形区大分子结晶和由纤维素Ⅱ转化两个过程。由纤维素Ⅱ明显地向纤维素Ⅵ转化的温度在230℃左右,并且发现这个转化温度随热处理的时间及张力而变化。经低温稀碱处理后,发现部分纤维素Ⅳ又会转变成纤维素Ⅱ。在190℃以下(包括190℃)热处理纤维的结构参数变化不大,但它的大部分性能变好。热处理温度高于190℃以上时,由于聚合度下降引起纤维强度降低。同时,实验得出纤维素Ⅳ的含量增加,有使纤维湿模量增大,而膨润度、吸湿率下降的趋势。这对改善粘胶纤维的性能有重要的作用。  相似文献   

10.
本文主要为了改善苎麻纱和麻棉纱的弹性,对苎麻纱、麻棉纱和棉纱进行了碱处理。并根据前人所做的工作,即有张力状态下碱处理和松弛状态下碱处理,其纱线性能存在较大差异,因而本文着重考虑在不同张力状态下进行碱处理,研究结果表明,采用低张力进行碱处理。其苎麻纱和麻棉纱的最大变形能力即断裂伸长显著增加,初始弹性模量显著下降,纱线变形恢复能力显著提高。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

13.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

14.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

18.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

19.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

20.
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